Search Result for "biosafety level 4":
Wordnet 3.0

NOUN (1)

1. exposure to exotic infectious agents that pose a high risk of life-threatening disease and can be transmitted as an aerosol and for which there is no vaccine or therapy; 



WordNet (r) 3.0 (2006):

biosafety level 4
    n 1: exposure to exotic infectious agents that pose a high risk
         of life-threatening disease and can be transmitted as an
         aerosol and for which there is no vaccine or therapy